1. Field of the Invention
This invention concerns dry formed, nonwoven webs and the treatment of such webs with surfactants.
2. Description of the Prior Art
Surfactants have been added to paper products mainly to result in a towel pretreated with a detergent surfactant. U.S. Pat. No. 3,897,356, inventor -- Alex Pociluyko entitled "Windshield Wipers Containing Nonionic Surfactant" is an example of a paper product pretreated with a detergent surfactant. However, the '356 patent does not suggest the concept of wet working a web after the surfactant has been added to the web.
U.S. Pat. No. 3,686,025 discloses impregnating an absorbent material with a softening agent which is releasable from said absorbent material at a controlled rate. The product is intended for use during standard laundering of textile fabrics. The controlled release of the softening agent is intended for releasing the softening agent during washing of textiles. Although column 5, beginning at line 30 of the '025 patent discloses impregnating an absorbent substrate, preferably a non-woven, water-laid or air-laid cloth. The patent disclosure does not suggest subsequent wet working or its effectiveness on the wipe dry property of a dry formed web.
U.S. Pat. No. 2,961,362 issued to Smith et al is representative of a large number of patents which disclose surface active agents applied to non-woven, dry-formed substrates. These patents are generally silent about the effectiveness of subsequent wet-working of the web or substrate and its effect upon the wipe dry characteristic of the web.